Cool huh? That means that the price on Harry's head set at 100,000 galleons is huge 2.5 MILLION dollars! It also means that butter beer comes in nice and cheap at $3 a bottle and wands are under $200 which is fair. It also shows just how generous Harry was with his wealth: giving the Weasley twins his 1,000 galleon/$25,000 Triwizard Tournament winnings to set up their joke shop and dropping a low-key 10 galleon each (equaling $750) on Omnioculars for himself, Ron and Hermione at the Quidditch World Cup.
Sadly it also shows how poor the Weasley's really were. In the Chamber of Secrets, there's a part where the family empty out their Gringott's vault for school supplies and the 1 galleon and a pile of sickles is only worth $50 to $75. They have to get ALL their kids books, robes and a wand for Ginny. That's insane! Makes you realise how bad Harry and Ron must have felt when they got a fine for the flying car that was 50 galleons...